Watercolor Techniques

Artist working



watercolor palette



Techniques

Watercolor painting has the reputation of being quite demanding; it is more accurate to say that watercolor techniques are unique to watercolor. Unlike oil or acrylic painting, where the paints essentially stay where they are put and dry more or less in the form they are applied, water is an active and complex partner in the watercolor painting process, changing both the absorbency and shape of the paper when it is wet and the outlines and appearance of the paint as it dries. The difficulty in watercolor painting is almost entirely in learning how to anticipate and leverage the behavior of water, rather than attempting to control or dominate it.

Many difficulties occur because watercolor paints do not have high hiding power, so previous efforts cannot simply be painted over; and the paper support is both absorbent and delicate, so the paints cannot simply be scraped off, like oil paint from a canvas, but must be laboriously (and often only partially) lifted by rewetting and blotting. This often induces in student painters a pronounced and inhibiting anxiety about making an irreversible mistake. Watercolor has a longstanding association with drawing or engraving, and the common procedure to curtail such mistakes is to make a precise, faint outline drawing in pencil of the subject to be painted, to use small brushes, and to paint limited areas of the painting only after all adjacent paint areas have completely dried.

Another characteristic of watercolor paints is that the carbohydrate binder is only a small proportion of the raw paint volume, and much of the binder is drawn between the hydrophilic cellulose fibers of wet paper as the paint (and paper) dries. As a result, watercolor paints do not form an enclosing layer of vehicle around the pigment particles and a continuous film of dried vehicle over the painting support, but leave pigment particles scattered and stranded like tiny grains of sand on the paper. This increases the scattering of light from both the pigment and paper surfaces, causing a characteristic whitening or lightening of the paint color as it dries. The exposed pigment particles are also naked to damaging ultraviolet light, which can compromise pigment permanency.

Watercolor paint is traditionally and still commonly applied with brushes, but modern painters have experimented with many other implements, particularly sprayers, scrapers, sponges or sticks, and have combined watercolors with pencil, charcoal, crayon, chalk, ink, engraving, monotype, lithography and collage, or with acrylic paint.

Many watercolor painters, perhaps uniquely among all modern visual artists, still adhere to prejudices dating from the 19th century rivalry between "transparent" and bodycolor painters. Among these are injunctions never to use white paint, never to use black paint, only to use transparent color, or only to work with "primary" color mixtures. In fact, many superb paintings flout some or all of these guidelines, and they have little relevance to modern painting practice.

Perhaps only with the exception of egg tempera, watercolor is the painting medium that artists most often compound themselves, by hand, using raw pigment and paint ingredients purchased from retail suppliers and prepared using only kitchen utensils. Even with commercially prepared paints, watercolor is prized for its nontoxic, tap ready solvent; lack of odor or flammability; prompt drying time; ease of cleanup and disposal; long shelf life; independence from accessory equipment (jars, rags, easels, stretchers, etc.). Its portability makes it ideal for plein air painting, and painters today can buy compact watercolor kits -- containing a dozen or more pan paints, collapsible brushes, water flask, brush rinsing cup and fold out mixing trays -- that fit neatly into a coat pocket.


Washes and glazes

Basic watercolor technique includes washes and glazes. In watercolors, a wash is the application of diluted paint in a manner that disguises or effaces individual brush strokes to produce a unified area of color. Typically, this might be a light blue wash for the sky. There are many techniques to produce an acceptable wash, but the student method is to tilt the paper surface (usually after fixing it to a rigid flat support) so that the top of the wash area is higher than the bottom, then to apply the paint in a series of even, horizontal brush strokes in a downward sequence, each stroke just overlapping the stroke above to pull downward the excess paint or water (the "bead"), and finally wicking up the excess paint from the last stroke using a paper towel or the tip of a moist brush. This produces an airy, translucent color effect unique to watercolors, especially when a granulating or flocculating pigment (such as viridian or ultramarine blue) is used. Washes can be "graded" or "graduated" by adding more prediluted paint or water to the mixture used in successive brush strokes, which darkens or lightens the wash from start to finish. "Variegated" washes, which blend two or more paint colors, can also be used, for example as a wash with areas of blue and perhaps some red or orange for a sky at sunrise or sunset.

A glaze is the application of one paint color over a previous paint layer, with the new paint layer at a dilution sufficient to allow the first color to show through. Glazes are used to mix two or more colors, to adjust a color (darken it or change its hue or chroma), or to produce an extremely homogenous, smooth color surface or a controlled but delicate color transition (light to dark, or one hue to another). The last technique requires the first layer to be a highly diluted consistency of paint; this paint layer dissolves the surface sizing of the paper and loosens the cellulose tufts in the pulp. Subsequent layers are applied at increasingly heavier concentrations, always using a small round brush, only after the previous paint application has completely dried. Each new layer is used to refine the color transitions or to efface visible irregularities in the existing color. Painters who use this technique may apply 100 glazes or more to create a single painting. This method is currently very popular for painting high contrast, intricate subjects, in particular colorful blossoms in crystal vases brightly illuminated by direct sunlight. The glazing method also works exceptionally well in watercolor portraiture, allowing the artist to depict complex flesh tones effectively.


Wet in wet

Wet in wet includes any application of paint or water to an area of the painting that is already wet with either paint or water. In general, wet in wet is one of the most distinctive features of watercolor painting and the technique that produces a striking painterly effect.

The essential idea is to wet the entire sheet of paper, laid flat, until the surface no longer wicks up water but lets it sit on the surface, then to plunge in with a large brush saturated with paint. This is normally done to define the large areas of the painting with irregularly defined color, which is then sharpened and refined with more controlled painting as the paper (and preceding paint) dries.

Wet in wet actually comprises a variety of specific painting effects, each produced through different procedures. Among the most common and characteristic:

Backruns (also called blossoms, blooms, oozles, watermarks or runbacks). Because the hydrophilic and closely spaced cellulose fibers of the paper provide traction for capillary action, water and wet paint have a strong tendency to migrate from wetter to drier surfaces of the painting. As the wetter area pushes into the dryer, it plows up pigment along its edge, leaving a lighter colored area behind it and a darker band of pigment along an irregular, serrated edge. Backruns can be subtle or pronounced, depending on the consistency of the paint in the two areas and the amount of moisture imbalance. Backruns can be induced by adding more paint or water to a paint area as it dries, or by blotting (drying) a specific area of the painting, causing the wetter surrounding areas to creep into it. Backruns are often used to symbolize a flare of light or the lighting contour on an object, or simply for decorative effect.

Paint Diffusion. Because of osmotic imbalance, concentrated paint applied to a prewetted paper has a tendency to diffuse or expand into the pure water surrounding it, especially if the paint has been milled using a dispersant (surfactant). This produces a characteristic feathery, delicate border around the color area, which can be enhanced or partially shaped by tilting the paper surface before the water dries, shaping the diffusion with surface water flow.
Pouring Color. Some artists pour large quantities of slightly diluted paint onto separate areas of the painting surface, then by using a brush, spray bottle of water and/or judicious tilting of the painting support, cause the wet areas to gently merge and mix. After the color has been mixed and allowed to set for a few minutes, the painting is tipped vertically to sheet off all excess moisture (the lighter colors across the darker ones), leaving behind a paper stained with random, delicate color variations, which can be further shaped with a wet brush or added paint while the paper is still wet. A popular variation uses separate areas of red, yellow and blue paint, which when mingled and drained produce a striking effect of light in darkness; areas of white are reserved by first covering them with plastic film, masking tape or a liquid latex resist. (The technique was actually invented, and used for similar effect, by J.M.W. Turner.)

Dropping In Color. In this technique a color area is first precisely defined with diluted paint or clear water, then more concentrated paint is dropped into it by touching the wet area with a brush charged with paint. The added paint can be shaped by tilting or stroking; backruns can be induced by adding pure water or concentrated paint, or the color can be lightened by wicking up paint with a moist brush. A striking, tesselated effect is produced when many precisely defined and interlocking areas are separately colored with this randomly diffusing technique.
Salt Texture. Grains of coarse salt, sprinkled into moist paint, produce small, snowflake like imperfections in the color. This is especially effective when the color area is a wash that displays the texture more clearly. A similar effect can be produced by spraying a moist (not shiny but still cool to the touch) paint area with water, using a spray bottle held two or three feet above the painting surface, or by sprinking a wet paint with coarse sand or sawdust.

Watercolor painters also learn to apply paint to paper and then, when the paint has dried to the right point, brush along the edge of the paint with a flat, mop or sky brush charged with a moderate amount of clear water. This new area of water pulls the wet paint outward in a diffusion fan that is controlled by judging the wetness of the paint and the amount of water applied; if excessive water is used, this brushing produces both an outward diffusion and a backrun into the drying paint. This method is useful to produce transitions in value or color within narrow bands, such as the locks of hair in a portrait head.


Drybrush

At the other extreme from wet in wet techniques, Drybrush is the watercolor painting technique for precision and control, supremely exemplified in many botanical paintings and in the drybrush watercolors of Andrew Wyeth. Raw (undiluted) paint is picked up with a premoistened, small brush (usually a #4 or smaller), then applied to the paper with small hatching or crisscrossing brushstrokes. The brush tip must be wetted but not overcharged with paint, and the paint must be just fluid enough to transfer to the paper with slight pressure and without dissolving the paint layer underneath. The goal is to build up or mix the paint colors with short precise touches that blend to avoid the appearance of pointilism. The cumulative effect is objective, textural and highly controlled, with the strongest possible value contrasts in the medium. Often it is impossible to distinguish a good drybrush watercolor from a color photograph or oil painting, and many drybrush watercolors are varnished or lacquered after they are completed to enhance this resemblance.

Scumbling (in the 19th century, called "crumbling color" or "dragging color") is an unrelated technique of loading a large, moist flat or round brush with concentrated paint, wicking out the excess, then lightly dragging the side or heel of the tuft across the paper to produce a rough, textured appearance, for example to represent beach grass, rocky surfaces or glittering water. The amount of texture that can be produced depends on the finish or tooth of the paper (R or CP paper works best), the size of the brush, the consistency and quantity of the paint in the brush, and the pressure and speed of the brush stroke. Moist paper will cause the scumbled color to diffuse slightly before it dries.


Diluting and mixing watercolor paints

When using watercolors, it is important to use the full range of paint consistency. The densest possible color is obtained by using the paint as it comes from the tube. The lightest color is obtained by using paint heavily diluted with water, or applied to the paper and then blotted away with a paper towel. Generally, paint directly from the tube should be used only with drybrush application: if the paint is used to completely cover the paper it typically dries to a dull, leathery appearance (called bronzing). Usually one part tube paint must be diluted with 2 to 3 parts water to eliminate bronzing in paint applied with a large brush to dry paper; with 4 to 6 parts water to produce the most saturated color; and with still more water to produce delicate tints of color and to enhance pigment textures (granulation or flocculation). The main point is to take advantage of the complete range of paint effects that are produced at different paint consistencies.

Tube paints are normally used with a flat palette that provides compartmentalized paint wells (for holding separate paint colors) and a large mixing area for mixing or diluting paints; pan paints are arrayed in enameled metal paint boxes that provide shallow mixing areas in the folding cover or in a fold out faceted tray. With tube paints, the excess paint remaining in the palette paint wells should be cleaned out only if the paint has become dirtied with another paint; otherwise the paints should be allowed to dry out promptly and completely, as this prevents mold from forming. Despite the common misconception, there is no visual difference between the viscous paint packaged in tubes and the dried paints in pans. Tube paints left to dry in paint wells are used in exactly the same way as pan paints -- the painter simply drips or sprays water over the paint a few minutes before starting work. The only notable difference is that some tube paints, such as viridian or cerulean blue, produce a gritty, uneven paint mixture when left to dry and then rewetted.

There are three finesses to color mixtures with watercolors. First, the raw or "pure" paint in the paint wells should never be discolored with any other paint. To ensure this, colors are mixed by picking up the desired quantity of dissolved paint from the prewetted paint well, using a moist, clean brush, then applying the paint onto the flat mixing area of the palette. Then the brush is rinsed before picking up any other paint. Once all paints are on the mixing area, they are mixed and/or applied to the painting.

Second, colors can be mixed in at least four ways: (1) by completely mixing together on the palette the paints that exactly match a desired color; (2) by loading together in a large brush the separate paints that approximately match the desired color, then letting these partially mix as the paint is applied to the paper; (3) by laying down first a single paint color, then "dropping in" the remaining paint colors with the brush while the painted area is still wet; (4) by glazing the paints as separate layers, one over another. Each technique has its purpose -- the first provides color accuracy (for photorealist painting), the second provides color variety (especially in dark colors), the third produces many "wet in wet" effects between wetter and drier paint areas (for greater color expressiveness), the fourth can produce a variety of luminous, iridescent or "broken color" effects, similar to mixtures with pastel chalks.

Third, watercolors should be used confidently: applied with a single stroke or joined strokes, then left alone to dry. Color muddiness or dullness typically comes from excessively brushing wet paint after it has been applied to the paper, or adding new layers of paint onto paper that has soaked water into its pulp (capillary action draws the paint inside the paper, dulling the color, rather than letting it dry on the surface). Overbrushing and "color soaking" are the most common flaws of novice watercolor paintings.


Minimal palettes

Palette is also the term for a specific selection of paints (or "colors") and, as a matter of economy, convenience or technique, painters have often preferred palettes comprising the smallest practical selection of paints. Many professional watercolorists work routinely with a palette of a dozen or fewer paints.

Though commercial watercolor brands offer selections of up to 100 or more paint colors in tubes, subtractive pigment mixtures can produce a complete range of colors from a small number of specific paints. In the 19th century a six paint "split primary" palette became popular and is still advocated by older painters. It is based on the three subtractive primary colors (red, yellow and blue), each in a "warm" and "cool" version:

"warm" yellow: Cadmium Yellow Medium (PY35)
"cool" yellow: Cadmium Lemon (PY35)
"warm" red: Cadmium Scarlet (PR108)
"cool" red: Quinacridone Carmine (PV19)
"warm" blue: Ultramarine Blue (PB29)
"cool" blue": Phthalo Blue (Green Shade) (PB15)
The reason for this intricate selection was that bright or saturated mixtures were only produced by related primary colors, e.g. the brightest orange is the mixture of a yellow with some red in it (warm yellow) and a red with some yellow in it (warm red); the brightest green is the mixture of a yellow with some blue in it (cool yellow) with a blue with some yellow in it (cool blue); duller mixtures are produced by mixing contrasted primaries, and the dullest mixtures by mixing three primaries.

The modern approach (the hexachrome palette) also relies on six paints, but spaces them more equally around the hue circle so that their mixtures automatically produce the most saturated color in every hue:

yellow: Cadmium Yellow Pale (PY35 or PY37) or Benzimidazolone Yellow (PY151 or PY154)
red orange: Pyrrol Orange (PO73) or Cadmium Scarlet (PR108)
magenta: Quinacridone Magenta (PR122) or Quinacridone Rose (PV19)
blue violet: Ultramarine Blue (PB29)
cyan: Phthalo Turquoise (PB16) or Phthalo Cyan (PB17)
green: Phthalo Green (PG7 Blue Shade or PG36 Yellow Shade)
Both palettes obtain dull or darkened colors, including a "neutral" (dark gray or black), by mixing together paints or colors on opposite sides of the hue circle -- especially orange or scarlet with cyan, and carmine or magenta with green.

As a matter of convenience, painters typically also add one or more paints made with an iron oxide pigment (the so called "earth" pigments, many of them manufactured as concrete colorants or wood stains) and sold under the names yellow ochre, raw sienna, raw umber, burnt sienna, burnt umber and/or venetian red. Exactly the same brown or ochre colors can be matched with either of the six paint palettes, but it tedious to do. As dark colors also require inconvenient mixing, most painters prefer to add a premixed dark neutral paint containing a carbon (black) pigment, usually sold under the marketing names indigo, payne's gray, neutral tint or sepia.


Paint Lightfastness

A final consideration is lightfastness, or the ability of a pigment to retain its original color appearance under exposure to light. This is usually indicated as a numerical rating, from I (high lightfastness) to III or IV (low lightfastness), on the paint tube or in the paint technical information available from the manufacturer. Lightfastness is a crucial issue with watercolors, because the paint pigment is not surrounded by a protective dried binder (as in oil or acrylic paints) but is left exposed on the surface of the paper. Watercolors acquired in the 19th century a market reputation for relative impermanence that continues to suppress their price today, and painters who admire this medium will make choices to improve its market status: in fact, lightfast watercolor paints on archival papers are as durable as any oil painting on canvas.

Unfortunately, paint manufacturer lightfastness ratings are not always trustworthy. However, because they have been demonstrated to be impermanent in watercolors, certain pigments (paints) should never be used under any circumstances. These include: aureolin (PY40), alizarin crimson (PR83), genuine rose madder (NR9), genuine carmine (NR4), genuine vermilion (PR106), most naphthol reds and oranges, all dyes (including most "liquid watercolors" and marker pens), and paints premixed with a white pigment, including paints marketed under the names naples yellow, emerald green or antwerp blue. Most of these are colorants invented in the 19th century or before that have been superseded by far more durable modern alternatives, and these are usually sold as "hue" paints (e.g., "alizarin crimson hue" is a modern pigment that resembles alizarin crimson). Industry labeling practice is to include a lightfastness rating on the paint packaging, and painters should only use paints that have a lightfastness rating of I or II under the testing standards published the American Society of Testing and Materials (now ASTM International).


References

History
Martin Hardie. Water-Colour Painting in Britain (3 volumes: I. The Eighteenth Century; II. The Romantic Period; III. The Victorian Period.). Batsford, 1966-1968. ISBN 113184131X
Michael Clarke. The Tempting Prospect: A Social History of English Watercolors. British Museum Publications, 1981. ASIN B000UCV0XO
Christopher Finch. Nineteenth-Century Watercolors. Abbeville Press, 1991. ISBN 1558590196
Christopher Finch. American Watercolors. Abbeville Press, 1991. ASIN B000IBDWGK
Christopher Finch. Twentieth-Century Watercolors. Abbeville Press, 1988. ISBN 089659811X
Andrew Wilton & Anne Lyles. The Great Age of British Watercolours (1750-1880). Prestel, 1993. ISBN 3-7913-1254-5
Anne Lyles & Robin Hamlyn. British watercolours from the Oppé Collection. Tate Gallery Publishing, 1997. ISBN 1-85437-240-8
Eric Shanes. Turner: The Great Watercolours. Royal Academy of Arts, 2001. ISBN 0-8109-6634-4

Tutorials & Technique
John Ruskin. The Elements of Drawing [1857]. Watson-Guptill, 1991. ISBN 0-8230-1602-1 (Reprints from other publishers are also available.)
Rex Brandt. The Winning Ways of Watercolor: Basic Techniques and Methods of Transparent Watercolor in Twenty Lessons. Van Nostrand Reinhold, 1973. ISBN 0-442-21404-9
Edgar A. Whitney. Complete Guide to Watercolor Painting. Watson-Guptill, 1974. [Dover Edition ISBN 0-486-41742-5]
Stan Smith. Watercolor: The Complete Course. Reader's Digest, 1995. ISBN 0-89577-653-7
David Dewey. The Watercolor Book: Materials and Techniques for Today's Artist. Watson-Guptill, 1995. ISBN 0-8230-5641-4
Pip Seymour. Watercolour Painting: A Handbook for Artists. Lee Press, 1997. ISBN 0-9524727-4-0
Charles LeClair. The Art of Watercolor (Revised and Expanded Edition). Watson-Guptill, 1999. ISBN 0-8230-0292-6
Curtis Tappenden. Foundation Course: Watercolour. Cassell Illustrated, 2003. ISBN 1844030822
Royal Watercolour Society. The Watercolour Expert. Cassell Illustrated, 2004. ISBN 1844031497

Materials
Jacques Turner. Brushes: A Handbook for Artists and Artisans. Design Press, 1992. ISBN 0830639756
Sylvie Turner. The Book of Fine Paper. Thames & Hudson, 1998. ISBN 0500018715
Ian Sideway. The Watercolor Artist's Paper Directory. North Light, 2000. ISBN 1581800347